1. Field of the Invention
The present invention relates to an implanted soft palate support, and more particularly to an implanted soft palate support and an implantation method for treating adult obstructive sleep apnea/hypopnea syndrome (OSAHS).
2. Related Art
Adult OSAHS is a sleep breathing disorder with clinical features of snoring and apnea caused by upper airway collapse and obstruction during sleep. The morbidity of OSAHS is about 4% among adult men and about 2% among adult women even according to the lowest diagnosis criteria, and OSAHS presents a serious threat to the life and health of patients.
As for the pathogenesis of OSAHS, it is generally considered that the main cause is that, pharyngeal muscles for maintaining the upper airway open relax during sleep, resulting in soft tissue collapse and obstruction, and the plane of obstruction is usually located in the soft palate, tonsil, and tongue root. Many methods for treating OSAHS exist, which include two types, that is, non-surgical treatment and surgical treatment.
Methods of Non-Surgical Treatment Mainly Include:
1. Continuous Positive Airway Pressure (CPAP), in which a breathing machine capable of continuously generating a positive pressure air is closely connected with the nose and face of a patient via a nasal mask, so as to prevent collapse and obstruction of the soft tissues of the airway during sleep. Though the method has a good effect, it is difficult for approximately ⅔ of the patients to adapt to the machine, and they cannot sleep when wearing the machine.
2. Oral appliance. A device is placed in an oral cavity to move forward the mandible or pull forward the tongue, so as to enlarge the pharyngeal cavity and release the airway obstruction during sleep. The method has many types and produces a certain effect, but most patients cannot adapt to it. The oral appliance leads to irritation and foreign body sensation, causing that the user cannot fall asleep, and may have temporo-mandibular joint injury with long term use.
For example, International Application PCT/US2005/00139, Jan. 3, 2005, has disclosed a method and a device for relieving upper airway obstructions. The device includes a mouthpiece that is adapted to form a sealed cavity within a human mouth. The patient bites the device during sleep, so as to form the sealed cavity within the oral cavity. A negative pressure generator is connected with the device. For a patient suffering from OSAHS, the device is effective to pull the patient's tongue and/or soft tissues of the upper airway up and away from the posterior pharyngeal wall to reopen the airway.
Chinese Utility Model Patent ZL200620110299.7 has disclosed a tongue forward-moving device for treating OSAHS and snoring. The tongue forward-moving device includes a semi-lunar base, in which a semi-lunar upper-tooth receiving groove formed by front and rear flanges is provided at an upper portion of the base; an arc-shaped rear baffle is provided at a bottom portion of the base, and a tongue anchoring hole running through front and rear edges is provided in the center of the base; and an arc-shaped front baffle is provided at the bottom portion of the base, and a bracket for a lower front dentition is formed between the front and rear baffles. The tongue forward-moving device provides a die for being actively bitten by a patient with upper and lower front dentitions, so that the upper and lower muscles are subconsciously in a relatively tension state during sleep, thereby forming a stable fulcrum between the maxilla and mandible and the tongue forward-moving device. The tongue anchoring hole provides a comfortable anchor station for the apex of tongue, and regulates the tongue between the tongue anchoring hole and the hyoid bone, so as to maintain a smooth airway at the mouth and pharynx, thereby achieving the objective of treating OSAHS and snoring.
Many patents similar to the device disclosed in International Application PCT/US2005/00139, Jan. 3, 2005, and the tongue forward-moving device disclosed in Chinese Utility Model Patent ZL200620110299.7 exist. All the patents use the teeth as a supporting point in the oral cavity, and various appliances are designed to change the tension state or position of the tongue or the soft palate during sleep, so as to achieve the objective of treating OSAHS and snoring. These appliances are placed in the oral cavity and are bitten and fixed before sleep, but since persons continuously change the posture and mouth shape during sleep, the appliances often cannot function effectively. In addition, it is uncomfortable and inconvenient for the patients to use the appliances.
Methods of Surgical Treatment Mainly Include:
1. Radiofrequency ablation, which is also referred to as low-temperature plasma radiofrequency ablation, and is a minimally invasive surgical method. An electronic de is penetrated into the soft tissues which cause airway obstruction, such as the soft palate, tonsil, and tongue root, and is electrified to induce tissue coagulation, necrosis, fibrosis, and contraction by heating. The method has a certain therapeutic effect, is effective for a slight case, has a poor long-term efficacy, and is ineffective for serious patients.
2. Palatopharyngoplasty. Since Fujita improved the Palatopharyngoplasty of Ikematus, a Japanese scholar, into uvulopalatopharyngoplasty (UPPP) and introduced it to the US in 1981, various improved technologies based on UPPP, including Simmons method, Fairbanks method, Dickson method, Woodson method, Z-palatoplasty (ZPP), uvulopalatal flap (UPF), H-uvulopalatopharyngoplasty (H-UPPP) have been successively reported in literatures, which made a great contribution to symptom alleviation and recovery of OSAHS patients. Countless patients benefit from the surgical treatment solution. However, in terms of long-term effect, since the mucous membrane and soft palate tissue structure are excessively removed, functional muscles are injured, resulting in complications of nasal regurgitation during swallowing, rhinolalia aperta, and nasopharyngeal stenosis and atresia. It is the leading edge and focus for the research and development of OSAHS treatment technologies nowadays to develop a method and corresponding surgical instruments which create a smaller wound or perform surgical treatment in a minimally invasive manner.
3. Soft palate implantation. International Application PCT/US2002/007966, Mar. 14, 2002, has disclosed a braided palatal implant for snoring treatment. In the invention, the implant is embedded in the soft palate to alter the center of gravity of the soft palate when swinging with the air flow and alter the aerodynamic characteristics of the soft palate, so as to increase the critical air flow speed at the soft palate and the pharynx, thereby preventing snoring from occurring. However, the method fails to prevent OSAHS from occurring, for OSAHS occurs when the soft palate collapses and obstructs the upper airway, so that the method and the adopted braided implant cannot be used to treat OSAHS. For serious patients, the risk of OSAHS is increased because the weight at the swinging portion of the soft palate is increased.
Based on the above, though generating a certain effect, the existing technologies and methods for treating OSAHS and snoring still have many defects, and have a poor long-term effect. Therefore, it is necessary to develop a new method and design a new instrument to treat OSAHS and snoring, in which the new method should create a wound as small as possible, and the new instrument should be safe, effective, simple, and reliable.